There is an increasing attention on an energy harvest technology to generate power by converting weak energy existing in various forms, such as heat, vibration, solar light and radio waves present in human life environment, and to utilize the power in a sensor network and the like. In the energy harvest technology, it is preferable to stabilize the power by storing the power in a secondary cell, since the power is generated from unstable energy such as solar light.
As for such a secondary cell, an all-solid-state secondary cell is available, which uses a solid electrolyte instead of an electrolyte solution. The all-solid-state secondary cell can be formed to be very thin and small by using a semiconductor process technology.
In the sensor network, the all-solid-state secondary cell described above and a power generating element are used as one electronic device, and power generated by the power generating element is stored in the all-solid-state secondary cell.
The electronic device including the all-solid-state secondary cell and the power generating element as described above has room for improvement in its miniaturization.
Note that techniques relating to the present application are disclosed in Japanese Laid-open Patent Publication No. 2008-103203, and Japanese Laid-open Patent Publication No. 04-331425.